I have done something really similar for about 10 Firms. I choice the Module way, where all Modules derive from one with the API. I call the modules never directly. They are created/loaded from the base module. 
my $m = Church->new('GeneralMotors') or die;
# $m is Church::GeneralMotors

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I'm very happy with this method. Propably you need nerly no code to implement Church::BMW derived from Church::GeneralMotors.
Boris

In reply to Re: Thorny design problem by borisz
in thread Thorny design problem by tlm

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